The present application relates to the examination and treatment of objects. It finds particular application in breast cancer, testicular cancer and/or prostate cancer detection and treatment. It also relates to other medical applications where imaging systems are used to identify tumors and/or other treatment regions of an object that are subsequently treated using radiation therapy systems.
Cancer is one of the leading causes of death in humans. Advancements in medical technologies have played an intricate role in both identifying tumors in the early stages and treating the tumors by either slowing their growth or shrinking tumors to a size that can safely be removed or possibly extinguished. These advancements have also identified techniques and/or systems that are less invasive and less uncomfortable to a patient undergoing treatment than techniques and/or systems used in years past.
Numerous techniques such as chemotherapy and radiation therapy have been developed to shrink and/or eradicate cancerous cells once they are detected. In radiation therapy, photons and/or particles are used to penetrate the patient's tissue and treat cancerous cells. Beams of photons and/or particles are targeted at the cancerous tumor and are configured to damage the DNA of tissue cells. Because tumors are generally not able to repair damaged DNA and/or repair damaged DNA more slowly than non-tumor cells, the beams may ultimately cause the cells to die (e.g., causing the tumor to shrink, possibly to the point of extinction).
The type of radiation therapy that is used to treat tumors generally depends upon the location of the tumor because particle treatment systems, while more controllable, are generally more costly to manufacture and operate. For example, tumors that are near and/or comprised within vital organs (e.g., such as the brain, spine, etc.) are generally treated with particle treatment systems because the energy of the radiation dose can be controlled (e.g., such that the energy peaks as the particle is passing through the cancerous cells while remaining relatively low before and/or after it impacts the cancerous cells). Tumors that are not as proximate to vital organs (e.g., such as breast cancer, prostate cancer, and/or other cancers that develop in a patient's extremities) are generally treated using photon therapy systems because less precision is required and because such treatments are relatively inexpensive.
It can be appreciated that before treating a patient with radiation therapy a treatment plan is generally developed to identify a specific target region. To generate a treatment plan, a patient is examined using an imaging apparatus (e.g., such as a computed tomography (CT) scanner, an MRI scanner, an ultrasound device, etc.). Such a treatment plan may specify the orientation of the tumor in the patient, the desired trajectory of the treatment beams relative to the patient, the dose of the radiation, etc., for example.
Typically, days, if not weeks, after the imaging is performed and the treatment plan is developed, the patient begins treatment. Radiographic treatments generally involve exposing the tumor, or a treatment region (e.g. which may be larger than the tumor) to radiographic photons (e.g., of a higher dose than the exposure during imaging) and/or radiographic particles.
While the existing techniques have proven effective for treating numerous types of tumors, there are some disadvantages. For example, the imaging and treatment do not generally occur concurrently, and thus the orientation of the tumor may vary slightly between the imaging and the treatment (e.g., the patient may be in a slightly different position during the treatment). Moreover, in some applications, the orientation of the patient differs because the imaging and the treatment are done with the patient at different positions. For example, with respect to breast cancer treatment applications, the imaging is generally performed with the patient in an upright position and the treatment is generally performed with the patient in a horizontal position (e.g., laying on her/his back). It will be appreciated to those skilled in the art that to compensate for such orientation changes in the tumor between the imaging and the treatment, the target or treatment area is generally larger than the actual tumor. Therefore, the patient is exposed to radiation that would be unnecessary if the orientation of the tumor could be more precisely known during the treatment.